1. Technical Field
The present invention relates to a technique of suppressing unevenness of an electro-optical device such as a liquid crystal device.
2. Related Art
In general, in an electro-optical device such as a liquid crystal device, pixel capacitors (liquid crystal capacitors) are arranged in intersections of scanning lines and data lines. To suppress voltage amplitudes of the data lines generated when the pixel capacitors are AC-driven, a technique in which common electrodes are provided for individual scanning lines (rows), and when selection voltages are applied to the scanning lines, the corresponding common electrodes are connected through transistors to power supply lines for supplying voltage corresponding to a writing polarity is known (refer to Japanese Unexamined Patent Application Publication No. 2005-300948).
However, in this technique, since the transistors are turned off in a non-selection period which is a period in which the selection voltages are not applied to the scanning lines, the common electrodes are not electrically connected, that is, the common electrodes are brought into voltage uncertain states (high impedance states). Therefore, since the common electrodes are influenced through parasitic capacitors by voltage changes of the data lines and noises, voltages of the common electrodes are readily varied. Since the rows are influenced by the variations of the voltages of the common electrodes, display unevenness represented by horizontal lines, is generated, and therefore, display quality is deteriorated.